Common Bacterial and Fungal Infection of the Skin

Question 1

Gram (+) cocci
Arranged in clusters
Most Pathogenic of all Staphylococci
Coagulase(+)
Catalase (+)
Has PROTEIN A (antiphagocytic)
beta hemolysis on BAP

Answer 1

Staphylococcus Aureus

Question 2

Superficial inflammation of hair follicles.

Small Erythematous papules/pustules associtaed with follicles

Answer 2

Folliculitis

Question 3

Commonly known as boil
Deeper form of folliculitis
Resolves upon spontaneous drainage

Answer 3

Furuncle

Question 4

When furuncles coalesce
Found in thick skin
May be seen in diabetic patients

Answer 4

Carbuncles

Question 5

Also called as ACNE INVERSA
disorder of the apocrine glands
Chronic disorder
Extensive scarrin, with multiple sinuses in and around the axilla

Answer 5

Hidradenitis Suppurutiva

Question 6

Yellowish crust on the skin

Answer 6

Impetigo

Question 7

Also called as ritter’s disease or pemphigus neonatorum
Generalized skin manifestation
Most aggressive form of Staphylococcal infection
The production of exfolatin by bacteria causues this syndrome

Answer 7

Staphylococcal Scalded Skin Syndrome

Question 8

Laboratory Dx of S. aureus

Answer 8

Gram stain: (+)
BAP and MSA
Coagulase and Catalase (+)

Question 9

treatment of S. aureus

Answer 9

Penicillin

or Vancomycin

Question 10

G(+) cocci in chains
Strict Parasite
Man is the only significant reservoir
Commonly presents as sore throat
Most serious Streptococcal pathogen
Sensitive bacitracin
Beta Hemolytic

Answer 10

Streptococcus pyogenes (Group A)

Question 11

The only significant reservoir for s. pyogenes

Answer 11

Man (nasopharyngeal)

Question 12

transmission of S. pyogenes

Answer 12

Direct/droplet

Question 13

Non infectious sequelae of S. pyogenes

Answer 13

RHD, AGN

Question 14

Impetigo in S. pyogenes

Answer 14

with yellow crusting

Question 15

Infection of epidermis which extends to the dermis, with characteristic “punched” out lesions

Answer 15

Ecthyma

Question 16

Shiny, swollen, red and painful
May become bullous
treated with 1st Gen cephalosporin

Answer 16

Cellulitis

Question 17

Deep seated infection
Emergency case
Violaceous discoloration of the skin
Swelling within 24-48 hours, acute infection
Lesions darken; 4th-5th day then becomes gangrenous

Answer 17

Necrotizing Fascitis

Question 18

Organisms associtaed with Nec Fas

Answer 18

peptostreptococci, Bacteroides, gram (-) rods and streptococcus

Question 19

Laboratory Dx of Streptococcus

Answer 19

G(+) cocci in chains
B-hemolysis
Bacitracin Sensitive (0.02 ug)
Screening Test: Latex Agglutination (Ig monoclonal to C- carbohydrate)

Question 20

Treatment for Streptococcus

Answer 20

Penicillin (cell wall inhibitors)

Low resistance against PEN (Benzathine Penicillin, Pen G or Pen V)

Alternative: Macrolides (Erythromycin)

Question 21

Hansen’s disease
Acid fast Bacillus
Cannot be cultured in vitro

Answer 21

Mycobacterium leprae

Question 22

M. Leprae can be propagated in

Answer 22

Nude mice (no T cells)
Monkey
9-banded armadillo

Question 23

Frequently affected nerves in Hansen’s disease

Answer 23

Median, Radial, ulnar, Popliteal, Perineal

Question 24

Paucibacillary

Answer 24

Strong CMIR
HIR normal
granuloma formation
Anesthetic
Not Infectious
treatment: 9 months

Question 25

Multibacillary

Answer 25

``` CMIR is weak (anergy) HIR Over reactive leads - Erythema nodosum leprossum No granuloma Infectious treatment : 3 years ```

Question 26

Signs and Symptoms of Hansen's disease

Answer 26

``` Area of discoloration Anesthesia Loss of hair in affected skin No sweating in the area Thickened nerve Area not pruritic Muscle Weakness ```

Question 27

treatment for Hansen's disease

Answer 27

Dapsone Rifampicin Clofaximine - darkening of the skin

Question 28

G(-) aerobic bacilli opportunistic pathogen grape like or tortilla odor in vitro Oxidase (+)

Answer 28

Pseudomonas Aeruginosa

Question 29

Definitive Diagnosis of p. Aeruginosa

Answer 29

Pyocyanin and fluorescein | Ability to grow at 42 degrees

Question 30

Paronychial infection that develop in individuals whose hands are frequently submerged in water

Answer 30

Green Nail syndrome

Question 31

occur in patients with decubitus ulcer, eczema and tinea pedis. These infections may have a Characteristic blue-green exudate and fruity odor

Answer 31

Secondary wound infections

Question 32

Pruritic follicular, maculopapular, vesicular or pustular lesions on any part of the body that was immersed in water

Answer 32

HOT TUB or swimming pool folliculitis

Question 33

Pseudomonal bacteremia produces well-recognized but uncommon distinctive skin lesion Hemorrhagic vesicles and pustules that evolve into necrotic ulcers

Answer 33

Ecthyma gangrenosum

Question 34

Treatment for P. aeruginosa

Answer 34

Double antibiotic therapy Surgical removal of eschars, debridement of necrotic tissue, or in severe cases, amputaion may be required

Question 35

Causative agent for Fish tank granuloma

Answer 35

M. marinum

Question 36

Skin abscesses at the site of self administered insulin injections n the thigh of a diabetic patient

Answer 36

M. chelonae

Question 37

tropical Ulcer

Answer 37

Fusobacterium fusiformis

Question 38

Gram(+) rod spore forming Skin infection with marked necrosis and edema of tissue

Answer 38

Bacillus anthracis

Question 39

Gas gangrene

Answer 39

Clostridium perfringens

Question 40

Animal bite infection

Answer 40

Pasteurella multicoda

Question 41

Anthrophilic fungus and is the most common and widely distributed dermatophyte of humans

Answer 41

Trichophytum rubrum

Question 42

Common saprophytic fungus believed to occur in soil, compost, humus, and on wood in humid tropical and subtropical regions. Familial spread of infection is reported

Answer 42

Tinea Nigra